1. Field of Invention
This invention relates to a projector which performs a keystone correction of an image during tilted projection.
2. Description of Related Art
Projectors project images onto screens. In some cases, projectors are set at a low position and project images onto screens that are set at a relatively higher position, which is called “tilted projections”. During the tilted projections, images projected on the screens are distorted to trapezoidal shapes from rectangular shapes due to an elevation angle in the tilted projection. Such a distortion is called “a keystone distortion”.
Related art projectors may include a special button and menu to correct the keystone distortion. A user can adjust the keystone distortion manually with this button and menu. Some related art projectors automatically detect the elevation angle and correct the keystone distortion in response to an instruction from the user.